despite the presence of pharmaceuticals in biosolids, due to the enhanced irreversible
sorption of pharmaceuticals to biosolids and subsequent decrease in bioavailability
to terrestrial organisms.
6 Uptake into Soil Invertebrates
As well as considering the uptake of pharmaceuticals into plants following land
application of pharmaceuticals, work has also evaluated the uptake of pharmaceuticals in soil invertebrates, albeit to a lesser extent. A majority of this work has
focussed on assessing uptake and accumulation in earthworms from spiked soil
under laboratory exposure conditions, although a small number of studies have
sampled earthworms from natural soils and have identified the presence of pharmaceuticals following land application of organic wastes. Earthworms represent an
ideal sentinel organism for assessing soil contamination, as they are in contact with
soil and soil solution, tend to migrate over only short distances and are widely
distributed in soils around the globe.
Pharmaceuticals were amongst a suite of 77 anthropogenic waste indicators
evaluated by Kinney et al. [102] across three agricultural fields in the Midwest
USA. The antibiotic trimethoprim was detected in earthworms sampled from the
biosolid- and manure-amended fields, at concentrations of 127 and 61 μg/kg,
respectively. Trimethoprim was notably not detected in the soils from which the
earthworms were sampled, thereby prohibiting the calculation of a bioaccumulation
factor (BAF). The largest BAF for all anthropogenic waste indicators evaluated in
this study was calculated at 27 for the personal care product, triclosan. Nevertheless,
this study documents that when pharmaceuticals are present in biosolids and swine
manures that are applied to agricultural land, these chemicals can be transferred to,
and accumulate in, earthworms, under realistic exposure scenarios.
More recently, Bergé and Vulliet [103] determined levels of pharmaceuticals in
earthworm samples collected from various soils around Lyon, France, to test their
recently developed simple, rapid and effective multi-residue method (QuEChERS
approach) for the determination of veterinary antibiotics and human contaminants in
earthworm tissue. Concentrations ranging between a few ng/g and 73.5 ng/g
(florfenicol) were observed for veterinary antibiotics, whilst concentrations for the
human pharmaceuticals paracetamol and fluvoxamine ranged from below the limit
of quantitation to 8.8 and 46.8 ng/g, respectively. Earthworms are in contact with the
soil surface and are therefore exposed to a variety of organic pollutants from human
activities, as evidenced by the results from the field sampling campaigns detailed
above. These results demonstrate exposure to a large number of organic micropollutants, including pharmaceuticals, in the wider environment following commonly adopted sustainable agricultural practices such as amendment with manure
and compost. For example, the earthworms analysed in the Bergé and Vulliet [103]
study were sampled from kitchen garden soils in receipt of widely available
compost.
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L. J. Carter et al.
sorption of pharmaceuticals to biosolids and subsequent decrease in bioavailability
to terrestrial organisms.
6 Uptake into Soil Invertebrates
As well as considering the uptake of pharmaceuticals into plants following land
application of pharmaceuticals, work has also evaluated the uptake of pharmaceuticals in soil invertebrates, albeit to a lesser extent. A majority of this work has
focussed on assessing uptake and accumulation in earthworms from spiked soil
under laboratory exposure conditions, although a small number of studies have
sampled earthworms from natural soils and have identified the presence of pharmaceuticals following land application of organic wastes. Earthworms represent an
ideal sentinel organism for assessing soil contamination, as they are in contact with
soil and soil solution, tend to migrate over only short distances and are widely
distributed in soils around the globe.
Pharmaceuticals were amongst a suite of 77 anthropogenic waste indicators
evaluated by Kinney et al. [102] across three agricultural fields in the Midwest
USA. The antibiotic trimethoprim was detected in earthworms sampled from the
biosolid- and manure-amended fields, at concentrations of 127 and 61 μg/kg,
respectively. Trimethoprim was notably not detected in the soils from which the
earthworms were sampled, thereby prohibiting the calculation of a bioaccumulation
factor (BAF). The largest BAF for all anthropogenic waste indicators evaluated in
this study was calculated at 27 for the personal care product, triclosan. Nevertheless,
this study documents that when pharmaceuticals are present in biosolids and swine
manures that are applied to agricultural land, these chemicals can be transferred to,
and accumulate in, earthworms, under realistic exposure scenarios.
More recently, Bergé and Vulliet [103] determined levels of pharmaceuticals in
earthworm samples collected from various soils around Lyon, France, to test their
recently developed simple, rapid and effective multi-residue method (QuEChERS
approach) for the determination of veterinary antibiotics and human contaminants in
earthworm tissue. Concentrations ranging between a few ng/g and 73.5 ng/g
(florfenicol) were observed for veterinary antibiotics, whilst concentrations for the
human pharmaceuticals paracetamol and fluvoxamine ranged from below the limit
of quantitation to 8.8 and 46.8 ng/g, respectively. Earthworms are in contact with the
soil surface and are therefore exposed to a variety of organic pollutants from human
activities, as evidenced by the results from the field sampling campaigns detailed
above. These results demonstrate exposure to a large number of organic micropollutants, including pharmaceuticals, in the wider environment following commonly adopted sustainable agricultural practices such as amendment with manure
and compost. For example, the earthworms analysed in the Bergé and Vulliet [103]
study were sampled from kitchen garden soils in receipt of widely available
compost.
202
L. J. Carter et al.